Ke1x Suspension Theory

[corolla_nut]

Hey

Been scrounging around for a while now, I've noticed people remove their transverse leaf spring and put heavier coils in the front of ke1x cars.

 

Is there any particular reason why the transverse leaf spring should be removed and normal macpherson struts put in?

 

I'm assuming that you can fit a whiteline swaybar to the front of the car and ke55/70 girlock calipers/discs on original struts without a huge headache? why go to the drama of taking the transverse spring out?

 

Everybody just says that they took it out, nobody explains why. That is the all important part of any discussion, why!

 

Robert/Kylie

[camerondownunder88]

Hi,

Front leaf is like a sway bar. So by putting in a sway bar it is over kill in a small car. This will cause the car to pick up the inside tire on the back around corners with both in and will smoke rubber for 100m up the street.

 

Take out leafs install sway bar.

 

Also sway bar with KE55/70 brake up grade will cause the sway bar to hit the brakes so that is only down side.

 

Cheers

Cameron

[parrot]

A mate who knows these things was telling me the other day that the recent Corvette had some issue with space in the front when designing it, and they got around it by using a fiberglass transverse leaf.

 

As soon as he started talking GMH I switched off, so a bit sparse on detail.

 

http://en.wikipedia.org/wiki/Corvette_leaf..._other_vehicles

[corolla_nut]

that makes sense. transverse leaf out, front swaybar in, coilovers in front with stiffer springs to make up for lack of transverse spring.

 

so what do you do for brakes if the ke55/70 girlock calipers no longer fit?

 

and how do we go about obtaining zero or slightly negative camber and shiteloads of caster?

 

Robert.

[phife]

It is a cheaper design as less other suspension/handling components are needed, but it does affect performance handling.

Basically when one side moves (bumps), the other is affected in someway. The thin coil springs hold no weight at all so they wont help.

 

Corvette have used this setup for years but have refined it very well.

Although alot of circuit racing vettes end up going with coilovers.

 

http://www.supersport.org.mk/Statii/Front%20Suspension.htm

http://www.carbibles.com/suspension_bible.html

http://www.carbibles.com/images/fibreglass_spring.gif

 

Edit: Related post on the Whitline swaybar

http://www.rollaclub.com/board/?showtopic=26302

Edited June 1, 2009 by phife

[Felix]

Front leaf is like a sway bar. So by putting in a sway bar it is over kill in a small car. This will cause the car to pick up the inside tire on the back around corners with both in and will smoke rubber for 100m up the street.

 

:bash: :y: That is what happens if you remove the front leaves, and fit ke2x coils WITHOUT a swaybar. Been there done that.

 

Edit: after rereading and trying to decipher Cams post, I think he is maybe talking about having swaybars both front and rear? I wouldn't bother with a rear bar, unless I was running either an LSD or locked diff.

 

There is nothing wrong with running a swaybar with the stock front leaf suspension setup. It is a MASSIVE improvement over stock, and I highly recommend it.

 

I've got a ke15 and ke16, both with the whiteline front bars. My ke15 has had a few different setups over the years.

 

I initially ditched the leaves and went to spaced ke3x HD front shocks with cut ke2x springs in an attempt to lower the front of the car (which didn't really make much difference). This removed 2 inches of droop, to match the shorter Tokico rear shocks it runs. It was VERY dicey before fitting a front swaybar. With the healthy little 4k in it and cheapy 155 tyres the car could easily arc up the inside rear for a good 100m or more up the road in the dry. It was super scary in the wet as with so much weight transfer the car would get sideways without even trying, and with such a narrow track/short wheelbase it was a major handful.

 

Fitting the front swaybar removed all the excess body roll, and helps keep the inner rear tyre on the ground during cornering. Coupled with a set of Yoky A539's the car totally changed personality. It made the handling neutral, in both the wet or dry it drove exactly the same. It was still scary, but in a totally different way... You could enter corners at ridiculously scary speeds and it would just want to go faster. LOL, it became frustrating on mountain roads because you were always catching bikes and having them slow you up through corners.

 

I did put the leaves back in for a while with cut stock coils. It handled much the same. The main difference is how the car handled on the edge. With the leaves the car is more suited to a point and squirt driving style... ie. you need to get all your braking over with before turn-in. If you overcook things the car is more prone to understeer. Sudden lift-off doesn't really change things to much.

 

Without leaves the car suits my driving style more allowing me to brake later down to the corner apex, and also less prone to understeer if you seriously over cook a corner. Sudden throttle liftoff makes the car suck-in back on line, but tend to tail out.

 

I'd fit a swaybar and go with the leaves until you get more used to how the car handles on the edge. I used to have a ke30 and those things are so much easier and less dicey to drive on the edge seeing the wheelbase/track is longer/wider.

 

Yes with the whiteline bars there is the issue with the swaybar hitting the calipers, and forcing fluid back to the mastercylinder, requiring you to pump the pedal a few times to regain brakes. I've found replacing pads more often reduces it happening. Also the ke1/2x calipers with the long thin pads are more affected. The jap ke3x calipers with the square pads are least affected. Winding the steering lock bolts out a bit helps.

Edited June 2, 2009 by Felix

[altezzaclub]

Photos!

 

Having not seen leaf springs since my 1949 Armstrong Siddeley its a bit hard to visualise...

 

Rob- Pm me with an address if I can pop around for a look over a cup of tea. We're in North Orange.

[Felix]

Here is a scan from a manual, which sorta gives you and idea of how it works.

[Hiro Protagonist]

A mate who knows these things was telling me the other day that the recent Corvette had some issue with space in the front when designing it, and they got around it by using a fiberglass transverse leaf.

 

 

Corvette have used this setup for years but have refined it very well.

Although alot of circuit racing vettes end up going with coilovers.

 

Corvettes have had transverse leaf springs at the rear since '63 (the C2), in addition to the multi-link/trailing arm setup, but they only introduced the front transverse leaf spring in '84 (the C4), and have had both since.

[corolla_nut]

so where does the whiteline swaybar hit the caliper? any photos? and does it only do this on full lock?

 

Robert.

[philbey]

One other thing to keep in mind is that your leaf-coil combination gives you a progressive rate spring setup. I'd like to see someone properly tune a leaf-coil setup!

[Rolliac]

Is there a limit to how low you can go with the leaf spring still in there?

 

Like my ke10 is so low I want roll center adjusters.

 

(I’m running whiteline sway bar and no leaf spring).

 

Would I be correct in saying the leaf spring acts as a spring and a sway bar?

 

Remember the ke10 coil springs are really thin. So if you take the leaf spring out you’ll need thicker coils. I’m just using cut ke20 coils but there not really stiff enough IMO.

 

Also I have the shorter stroke ke30 strut inserts but my springs still are a long way from captive. I would like to find even shorter stroke strut inserts and cut down the struts like the AE86 and KE70 drift guys do.

 

As for caster and camber you could use adjustable strut tops but you won’t get much adjustment without coilovers because the top spring seat will hit the strut tower.

[rob83ke70]

Ok time to throw a spanner in the works.

 

With the leaf spring installed in the front end, a good proportion of weight is taken on the chassis rails, as opposed to the strut tops, like the newer models. If you take the leaves out, and put heavier springs in, the weight would then sit on the strut tops, and toyota didn't originally design this, so I'm thinking the strut towers might require some more reinforcing. It did occur to me the other day that the leaves may also affect the stress upon the lower control arms.

 

I'm not interested in lowering the car, or putting huge wheels on it or anything like that. I just want something that will handle acceptably and not break if I give it a bit of a hard time on the rough stuff.

 

I'm still a little bit confuzzled about the whiteline swaybar hitting the brake calipers, surely they couldn't release a suspension item that had a safety issue like that? Anybody have pics?

 

Robert.

[Felix]

Yep you are right about how the forces take a different path. I've had no issues running without the leaves. The strut towers have those reinforcement braces running to the firewall. There is no cracking or anything with mine and I have been running without leaves for a good 5 years or so.

 

If you think about it, not having the leaves would reduce loads on the lower control arm bushes. I guess also the swaybar shares twisting forces and feeds them into the chassis as well. Though obviously not with two wheel bumps.

 

As for the swaybars hitting the calipers, I found an old pic from my ke16 where you should be able to get the idea. You can see the lighter brown rub marks on the lower side of back the caliper.

[Rolliac]

Did any one find a cure for the caliper/ sway bar issue?

 

I remember someone saying they mounted the calipers the other way round but didn’t see any evidence. Then someone said they had adjustable control arms but again no evidence.

 

Longer control arms would be cool coz there’d be more room between the caliper and sway bar plus the extra camber would come in handy.

 

Does anyone else find they wear the outside edge of the front tires on ke10? I’m guessing it’s because I’m always strapping it round corners and don’t have enough camber.